Review: emission and absorption of greenhouse gases by soils. Ecological problems

Soils are a source and sink of greenhouse gases (GHG) such as carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). Since the volumes of concentration and flux can be large, accurate quantitative estimates are needed to obtain the data on global GHG fluxes required for forecasting global changes and climate studies. This review shows the role of soils as one of the important sources and regulators of the content of CH4, CO2, N2O in the troposphere, and also presents the main methods for monitoring greenhouse gases. The influence of natural and anthropogenic factors on the emission and absorption of CH4, CO2, N2O by the soil cover has been analyzed. Original diagrams are presented showing the global fluxes of CH4, CO2, N2O by various ecosystems, including the pedosphere. The estimation of methane emission and distribution of its content in the main types of soils of the Rostov region is carried out. The mechanisms of CH4, CO2, N2O generation in soils and their possible influence on the calcium-carbonate balance, which plays an important role in the regulation of biogeochemical processes in the pedosphere, are considered. The performed analysis and generalization of research data on various types of soils makes it possible to shed light not only on their contribution to the global methane emission, but also to approach the understanding of processes and parameters that are important from the point of view of agrochemistry, such as, in fact, carbonate-calcium equilibrium and redox potential in modern soils. An inventory of sources and an assessment of the inter-reservoir gas mass transfer in the pedosphere - atmosphere system allows one to start developing a strategy to reduce greenhouse gas emissions that will help curb the rate of global climate change.